I have been testing the Kentli rechargeable batteries for use in our XD-v70 wireless microphones. We were throwing away batteries when they got down to 3 hours and it just seemed wasteful. I was wondering if anyone else has tried these batteries and what their results were. They are available from Amazon. These are Lithium-ion batteries that must have a voltage regulator in them to supply the normal 1.5 volts. I just recharge them when the microphone shows a drop in the amount of time left. Due to the voltage regulator, I believe that they would provide the full 1.5 volts until they are almost dead.